ATerm

_ATerm_
_aterm_

This collection provides one file:

 _aterm.ss_: reads input in ATerm plain text format.

This library provides utilities for manipulating the ATerm format.

See:

  - XXX

======================================================================

DATA DEFINITIONS -----------------------------------------------------

An aterm is one of:

  - sexp
  - annotated

> (struct annotated (term annotation)) :: sexp * aterm

Represents an ATerm annotated with the "{ ... }" syntax (see below).

PROCEDURES -----------------------------------------------------------

> (make-aterm-reader in) :: input-port -> (-> sexp)

Produces a thunk that reads an ATerm as an S-expression from the given
input port.

The translation of ATerms is given recursively over the grammar
given at:

    http://nix.cs.uu.nl/dist/stratego/strategoxt-manual-unstable-latest/manual/chunk-chapter/ref-baffle.html

The translation function [| -- |] is specified as follows:

  t :
    [| bt |]                 -> S-expression
    [| bt { t } |]           -> (make-annotated [| bt |] [| t |])

  bt :
    [| C |]                  -> symbol
    [| C(t1,...,tn) |]       -> (list [| C |] [| t1 |] ... [| tn |])
    [| (t1,...,tn) |]        -> (list [| t1 |] ... [| tn |])
    [| [t1,...,tn] |]        -> (list 'list [| t1 |] ... [| tn |])
    [| "ccc" |]              -> string
    [| int |]                -> integer
    [| real |]               -> (not implemented)
    [| blob |]               -> (not implemented)

> (unescape str) :: string -> string

Interprets the following escape sequences in a string:

  \a : alarm (ASCII 7)
  \b : backspace (ASCII 8)
  \t : tab (ASCII 9)
  \n : newline (ASCII 10)
  \v : vertical tab (ASCII 11)
  \f : formfeed (ASCII 12)
  \r : return (ASCII 13)
  \e : escape (ASCII 27)
  \\ : backslash (ASCII 92)

All other escaped letters are escaped to themselves, i.e., the initial 
backslash is removed.